The present invention is concerned with an apparatus for the initiation of spinning a thread on an open-end spinning apparatus and with an appropriate rotor cover therefor.
It is common knowledge, during the initial stages of spinning, to release the fiber band feed to the opening roll, to divert and lead the fibers away from the conventionally followed operational path during the normal spinning procedure, and to do so before said fibers reach the spin rotor. The fibers are only brought back to the spin rotor at an appropriate time. This is done so that, for the initiation of spinning fibers onto a thread end which has been introduced into the spin rotor, the fibers find more faultless conditions for incorporating themselves into a thread in the said spin rotor (WO 86/01235).
For this purpose, there is provided in an encapsulating wall of the housing which contains the opening roll, a suction opening, located in the fiber transport direction toward the opening of the fiber feed conduit. To this said opening, a connection piece is sealingly joined. A suction line can be added to this connection piece by, for example, being brought to the location of connection by a service unit.
The spin rotor is, as a rule, covered with an enclosure. For the maintenance of the open-end spinning apparatus, this enclosure must be swung away, so that, in turn, the spin cover can be opened, thus making the spin rotor accessible. The connection piece must give clearance to the swinging radius of the rotor cover. To this purpose, the connection piece has such a type of break-away sealing with an enclosure fitting, that upon pivoting the enclosure away, said connection piece is lifted from the said suction line.
When the enclosure is again swung back into its operational position, the connection piece is brought again into a tight sealed contact on the suction opening.
Evidence, however, has surfaced, indicating that the suction opening in the enclosure wall of the housing which encapsulates the opening roll, promotes wall deposition of fiber. If this occurs, upon the release of a fiber stream into the spin rotor system, these lump forming fibers carry through and get into the spin rotor where they interfere with the orderly initiation of spinning, that is, obstruct the spinning of a thread. In addition to this, there is the danger that fibers in the narrow zone between suction opening and the connection piece adhere to the walls in a hard deposition. This leads to a break in the sealed security and damage to the sealing means already in place. This impairs the functional and operational ability of the equipment. Beyond the danger that such disturbances are possible, the conventional apparatus is complex in construction and consequently expensive in cost and space.